Gender factor in hematopoietic stem cell transplantation

Abstract

of studies concerning metabolic, immunological and other diff erences between males and caused by their diff erential hormonal and background. However, few studies are dedicated to sex-dependent diff erences in amounts of donor hematopoietic cells used for stem cell transplantation (HSCT), kinetics of cytostatic drugs used for conditioning treatment and immunosuppressors for GvHD prophylaxis, as well as diff erences in common posttransplant complications. Th e following differences signifi cant for evaluation of HSCT results may be derived from previous studies: (1) Higher counts of CD34+ cells in hematopoietic graft s from males compared to female donors; (2) Metabolism of cytostatic drug in females suggest a tendency for decreased clearance and higher modifi cation rates due to increased CYP3A activities, along with decreased drug effl ux from target cells, thus suggesting higher accumulation of active cytostatic metabolites in female patients; (3) More eff ective and stable humoral immune response in females compared to males could be translated into better anti-infectious response, along with higher risk of chronic GvHD in females aft er allo-HSCT; (4) Male patients with some hematological malignancies subjected to allo-HSCT are more prone to posttransplant relapses, however, confl icting data are reported; (5) Increased risk of acute GvHD in males exists in cases of allo-HSCT from female donors. Th e issue of graft -versus-leukemia eff ect in this setting still remains open. In sum, estrogen hormones seem to be to the most probable cause of gender diff erences in HSCT-associated risks. However, modifying role of sex steroids is not well studied, and it should vary, depending on the age of patients. Th erefore, real signifi cance of sex diff erences in HSCT deserves further extensive studies in large databases.